Rhenium

01 / A closer look

Meet Rhenium

Rhenium has atomic number 75: every atom of this element contains 75 protons. It belongs to period 6, group 7 of the periodic table.

In a neutral atom, the number of electrons equals the number of protons. Isotopes of this element share the same atomic number but have different neutron counts.

02 / Physical properties

Melting point

3458 K

Boiling point

5863 K

Density

20.8 g/cm³

Atomic weight

186.21 ± 0.01

Melting points, boiling points and densities follow RSC fact boxes. Density is referenced to room temperature; consult the source for pressure and allotrope details. These are reference values, not a claim that every value was experimentally measured. Atomic weights follow CIAAW.

Physical-property source: Royal Society of Chemistry ↗ · Reviewed 24 September 2026

Standard atomic weights follow CIAAW 2024 (abridged). Brackets show an isotope mass number from IUPAC 2022, not a standard atomic weight.

03 / Atomic structure

Atomic structure

Electron configuration

[Xe]6s2 4f14 5d5

Oxidation states

+7, +6, +4

Electronegativity · Pauling

1.9

First ionisation energy

7.88 eV

Atomic radius

217 pm

04 / Where it is found

Where it is found

Trace quantities associated with molybdenum ores.

Production and export figures depend on the commodity and reporting year. No comparable country quantities have been included for this element in this edition.